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## Homework Statement

A tank contains `100` kg of salt and `2000` L of water. A solution of a concentration `0.025` kg of salt per liter enters a tank at the rate `6` L/min. The solution is mixed and drains from the tank at the same rate.

Find the equation for the amount of salt in the tank after t hours.

## The Attempt at a Solution

I have 0.15kg/min as my rate in and y(t)/333.33 as my rate out.

Which I put together in the form

dy/dt = (5 - y(t))/(333.33)

Split it into

int of (dy/5 - y) = int of (dt/333.33)

-ln(5 - y) = t/333.33 + C

y(0) = 100, so C = -ln(-95)

-ln(5 - y) = t/(333.33) - ln(-95)

5 - y = -95e^(-t/333.33)

y(t) = 5 + 95e^(-t/333.33)

But that's wrong. I know I've asked alot of stuff today, but this one is driving me crazy, I've tried everything I could think of and nothing came out right. Help!